From: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
To: David Gibson <david@gibson.dropbear.id.au>
Cc: aik@ozlabs.ru, qemu-devel@nongnu.org, groug@kaod.org,
paulus@ozlabs.org, qemu-ppc@nongnu.org, ganeshgr@linux.ibm.com
Subject: Re: [PATCH v14 6/7] migration: Include migration support for machine check handling
Date: Wed, 25 Sep 2019 11:42:02 +0530 [thread overview]
Message-ID: <c1e3c599-5b29-c7f8-5b54-82e47d4b427a@linux.vnet.ibm.com> (raw)
In-Reply-To: <20190925013914.GI17405@umbus>
On Wednesday 25 September 2019 07:09 AM, David Gibson wrote:
> On Wed, Sep 18, 2019 at 01:42:51PM +0530, Aravinda Prasad wrote:
>> This patch includes migration support for machine check
>> handling. Especially this patch blocks VM migration
>> requests until the machine check error handling is
>> complete as these errors are specific to the source
>> hardware and is irrelevant on the target hardware.
>>
>> Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
>> ---
>> hw/ppc/spapr.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++
>> hw/ppc/spapr_events.c | 16 +++++++++++-
>> hw/ppc/spapr_rtas.c | 2 ++
>> include/hw/ppc/spapr.h | 2 ++
>> 4 files changed, 82 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>> index 6992b32..a72a4b1 100644
>> --- a/hw/ppc/spapr.c
>> +++ b/hw/ppc/spapr.c
>> @@ -46,6 +46,7 @@
>> #include "migration/qemu-file-types.h"
>> #include "migration/global_state.h"
>> #include "migration/register.h"
>> +#include "migration/blocker.h"
>> #include "mmu-hash64.h"
>> #include "mmu-book3s-v3.h"
>> #include "cpu-models.h"
>> @@ -1829,6 +1830,8 @@ static void spapr_machine_reset(MachineState *machine)
>>
>> /* Signal all vCPUs waiting on this condition */
>> qemu_cond_broadcast(&spapr->mc_delivery_cond);
>> +
>> + migrate_del_blocker(spapr->fwnmi_migration_blocker);
>> }
>>
>> static void spapr_create_nvram(SpaprMachineState *spapr)
>> @@ -2119,6 +2122,60 @@ static const VMStateDescription vmstate_spapr_dtb = {
>> },
>> };
>>
>> +static bool spapr_fwnmi_needed(void *opaque)
>> +{
>> + SpaprMachineState *spapr = (SpaprMachineState *)opaque;
>> +
>> + return spapr->guest_machine_check_addr != -1;
>> +}
>> +
>> +static int spapr_fwnmi_post_load(void *opaque, int version_id)
>> +{
>> + SpaprMachineState *spapr = (SpaprMachineState *)opaque;
>> +
>> + if (spapr_get_cap(spapr, SPAPR_CAP_FWNMI_MCE) == SPAPR_CAP_ON) {
>> +
>> + if (kvmppc_has_cap_ppc_fwnmi()) {
>> + return 0;
>> + }
>> +
>> + return kvmppc_set_fwnmi();
>> + }
>
> I don't see that you need this. The spapr caps need to be set the
> same on source and destination (the caps infrastructure handles that),
> so setup should already be handled by the caps .apply hooks.
Will check.
>
>> +
>> + return 0;
>> +}
>> +
>> +static int spapr_fwnmi_pre_save(void *opaque)
>> +{
>> + SpaprMachineState *spapr = (SpaprMachineState *)opaque;
>> +
>> + /*
>> + * With -only-migratable QEMU option, we cannot block migration.
>> + * Hence check if machine check handling is in progress and print
>> + * a warning message.
>> + */
>> + if (spapr->mc_status != -1) {
>> + warn_report("A machine check is being handled during migration. The"
>> + "handler may run and log hardware error on the destination");
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static const VMStateDescription vmstate_spapr_machine_check = {
>> + .name = "spapr_machine_check",
>> + .version_id = 1,
>> + .minimum_version_id = 1,
>> + .needed = spapr_fwnmi_needed,
>> + .post_load = spapr_fwnmi_post_load,
>> + .pre_save = spapr_fwnmi_pre_save,
>> + .fields = (VMStateField[]) {
>> + VMSTATE_UINT64(guest_machine_check_addr, SpaprMachineState),
>> + VMSTATE_INT32(mc_status, SpaprMachineState),
>> + VMSTATE_END_OF_LIST()
>> + },
>> +};
>
> So, I know I suggested earlier that you postpone the migration support
> to a later patch in the series. But at least for the actual vmstate
> stuff, I think that was due to considerations that have since gone. I
> don't see any reason you can't put this in as soon as you add the
> machine_check_addr and mc_status fields.
>
> The migration blocker stuff might have to come in a later patch, but
> that's ok.
I feel I can retain this. Let me know if you want me to change.
Regards,
Aravinda
>
>> +
>> static const VMStateDescription vmstate_spapr = {
>> .name = "spapr",
>> .version_id = 3,
>> @@ -2152,6 +2209,7 @@ static const VMStateDescription vmstate_spapr = {
>> &vmstate_spapr_dtb,
>> &vmstate_spapr_cap_large_decr,
>> &vmstate_spapr_cap_ccf_assist,
>> + &vmstate_spapr_machine_check,
>> NULL
>> }
>> };
>> @@ -2948,6 +3006,11 @@ static void spapr_machine_init(MachineState *machine)
>> exit(1);
>> }
>>
>> + /* Create the error string for live migration blocker */
>> + error_setg(&spapr->fwnmi_migration_blocker,
>> + "A machine check is being handled during migration. The handler"
>> + "may run and log hardware error on the destination");
>> +
>> /* Register ibm,nmi-register and ibm,nmi-interlock RTAS calls */
>> spapr_fwnmi_register();
>> }
>> diff --git a/hw/ppc/spapr_events.c b/hw/ppc/spapr_events.c
>> index ecc3d68..71caa03 100644
>> --- a/hw/ppc/spapr_events.c
>> +++ b/hw/ppc/spapr_events.c
>> @@ -43,6 +43,7 @@
>> #include "qemu/main-loop.h"
>> #include "hw/ppc/spapr_ovec.h"
>> #include <libfdt.h>
>> +#include "migration/blocker.h"
>>
>> #define RTAS_LOG_VERSION_MASK 0xff000000
>> #define RTAS_LOG_VERSION_6 0x06000000
>> @@ -844,6 +845,8 @@ void spapr_mce_req_event(PowerPCCPU *cpu, bool recovered)
>> {
>> SpaprMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
>> CPUState *cs = CPU(cpu);
>> + int ret;
>> + Error *local_err = NULL;
>>
>> if (spapr->guest_machine_check_addr == -1) {
>> /*
>> @@ -873,8 +876,19 @@ void spapr_mce_req_event(PowerPCCPU *cpu, bool recovered)
>> return;
>> }
>> }
>> - spapr->mc_status = cpu->vcpu_id;
>>
>> + ret = migrate_add_blocker(spapr->fwnmi_migration_blocker, &local_err);
>> + if (ret == -EBUSY) {
>> + /*
>> + * We don't want to abort so we let the migration to continue.
>> + * In a rare case, the machine check handler will run on the target.
>> + * Though this is not preferable, it is better than aborting
>> + * the migration or killing the VM.
>> + */
>> + warn_report_err(local_err);
>> + }
>> +
>> + spapr->mc_status = cpu->vcpu_id;
>> spapr_mce_dispatch_elog(cpu, recovered);
>> }
>>
>> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
>> index b569538..c652ec3 100644
>> --- a/hw/ppc/spapr_rtas.c
>> +++ b/hw/ppc/spapr_rtas.c
>> @@ -50,6 +50,7 @@
>> #include "hw/ppc/fdt.h"
>> #include "target/ppc/mmu-hash64.h"
>> #include "target/ppc/mmu-book3s-v3.h"
>> +#include "migration/blocker.h"
>>
>> static void rtas_display_character(PowerPCCPU *cpu, SpaprMachineState *spapr,
>> uint32_t token, uint32_t nargs,
>> @@ -446,6 +447,7 @@ static void rtas_ibm_nmi_interlock(PowerPCCPU *cpu,
>> */
>> spapr->mc_status = -1;
>> qemu_cond_signal(&spapr->mc_delivery_cond);
>> + migrate_del_blocker(spapr->fwnmi_migration_blocker);
>> rtas_st(rets, 0, RTAS_OUT_SUCCESS);
>> }
>>
>> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
>> index dada821..ea7625e 100644
>> --- a/include/hw/ppc/spapr.h
>> +++ b/include/hw/ppc/spapr.h
>> @@ -217,6 +217,8 @@ struct SpaprMachineState {
>>
>> unsigned gpu_numa_id;
>> SpaprTpmProxy *tpm_proxy;
>> +
>> + Error *fwnmi_migration_blocker;
>> };
>>
>> #define H_SUCCESS 0
>>
>
--
Regards,
Aravinda
next prev parent reply other threads:[~2019-09-25 6:13 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-18 8:12 [Qemu-devel] [PATCH v14 0/7] target-ppc/spapr: Add FWNMI support in QEMU for PowerKVM guests Aravinda Prasad
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 1/7] Wrapper function to wait on condition for the main loop mutex Aravinda Prasad
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 2/7] ppc: spapr: Introduce FWNMI capability Aravinda Prasad
2019-09-25 1:12 ` David Gibson
2019-09-25 5:42 ` Aravinda Prasad
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 3/7] target/ppc: Handle NMI guest exit Aravinda Prasad
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 4/7] target/ppc: Build rtas error log upon an MCE Aravinda Prasad
2019-09-25 1:30 ` David Gibson
2019-09-25 6:01 ` Aravinda Prasad
2019-09-25 6:16 ` Greg Kurz
2019-09-25 6:48 ` David Gibson
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 5/7] ppc: spapr: Handle "ibm, nmi-register" and "ibm, nmi-interlock" RTAS calls Aravinda Prasad
2019-09-25 1:33 ` David Gibson
2019-09-25 6:04 ` Aravinda Prasad
2019-09-18 8:12 ` [Qemu-devel] [PATCH v14 6/7] migration: Include migration support for machine check handling Aravinda Prasad
2019-09-25 1:39 ` David Gibson
2019-09-25 6:12 ` Aravinda Prasad [this message]
2019-09-18 8:13 ` [Qemu-devel] [PATCH v14 7/7] ppc: spapr: Activate the FWNMI functionality Aravinda Prasad
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=c1e3c599-5b29-c7f8-5b54-82e47d4b427a@linux.vnet.ibm.com \
--to=aravinda@linux.vnet.ibm.com \
--cc=aik@ozlabs.ru \
--cc=david@gibson.dropbear.id.au \
--cc=ganeshgr@linux.ibm.com \
--cc=groug@kaod.org \
--cc=paulus@ozlabs.org \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).